Electronic devices with component mounting structures

ABSTRACT

Electronic devices are provided that have components. A housing protrusion may be interposed between a display cover layer and display components. A button may have a button member. A support structure for a dome switch in the button may have a screw hole. A housing may have screw holes through which a screw passes. The screw may also pass through the screw hole of the support structure to hold the switch structure near the button member. A clip may have a spring. A metal plate may prevent the clip from becoming worn by the spring. A display may be mounted on a ledge in a device housing. The ledge may have gaps with supports and removed corners.

This application is a division of U.S. patent application Ser. No.14/605,864, filed Jan. 26, 2015, which is a division of U.S. patentapplication Ser. No. 14/094,600, filed Dec. 2, 2013, now U.S. Pat. No.8,982,547, which is a division of U.S. patent application Ser. No.12/870,769, filed Aug. 27, 2010, now U.S. Pat. No. 8,611,077, which arehereby incorporated by reference herein in their entireties. Thisapplication claims the benefit of and claims priority to U.S. patentapplication Ser. No. 14/605,864, filed Jan. 26, 2015, U.S. patentapplication Ser. No. 14/094,600, filed Dec. 2, 2013, now U.S. Pat. No.8,982,547, and U.S. patent application Ser. No. 12/870,769, filed Aug.27, 2010, now U.S. Pat. No. 8,611,077.

BACKGROUND

This relates generally to electronic devices, and, more particularly, toelectronic device component mounting features that enhance theperformance of electronic devices.

Electronic devices may have displays. Displays may be mounted near tothe edges of device housings.

Buttons are used in electronic devices to control device functions suchas media playback functions. Buttons are typically mounted in openingsin device housings.

Spring-loaded clips may be provided on electronic devices that allow thedevices to be attached to items of clothing. Clips may be mounted todevice housings using hinges.

Displays may be provided with cover glass layers that rest on housingledges. The housing ledges may have gaps to accommodate structures suchas screws.

Electronic devices with features such as these may have shortcomings.Device housings may not be configured in a way that allows displays tobe placed sufficiently close to device housing edges, button mountingstructures may be overly large, spring-loaded clips may have parts thatare subject to undesired wear, and display cover layers may be subjectto unwanted damage when devices are dropped.

It would therefore be desirable to be able to provide improvedelectronic device structures.

SUMMARY

A housing for an electronic device may have a protrusion that isinterposed between a display cover layer and display components. Thedisplay cover layer may be a layer of cover glass. The displaycomponents may include a flex circuit cable and a driver integratedcircuit. The protrusion may lie over a cavity in a housing. The flexcircuit may have a bent portion that is supported by a support structurewithin the cavity. Capacitors on the flex circuit may be mounted in thecavity.

A button may have a button member. A device housing may have an openingthrough which the button member passes. A support structure may beprovided for a switch such as a dome switch. The dome switch may beactuated when the button member is pressed. The support structure forthe dome switch may have a screw hole. A housing may have screw holesthrough which a screw passes. The screw may also pass through the screwhole in the support structure. This holds the switch structure near thebutton member.

An electronic device may have a clip. The clip may have a clip memberthat is attached to a housing structure in the electronic device by ahinge. The hinge may have a torsion spring. A metal plate in the hingemay be interposed between the clip member and the spring to prevent theclip member from becoming worn by the spring.

A display may be mounted on a ledge in a device housing. The ledge mayhave a ledge surface and gaps.

Support structures may be provided in the gaps. The support structuresmay have recesses that accommodate screws in the device. The supportstructures may have upper surfaces that lie flush with the ledgesurface.

Further features of the invention, its nature and various advantageswill be more apparent from the accompanying drawings and the followingdetailed description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an illustrative electronic device thatmay be provided with a display and display mounting structures inaccordance with an embodiment of the present invention.

FIG. 2 is a cross-sectional side view of an electronic device of thetype shown in FIG. 1 in accordance with an embodiment of the presentinvention.

FIG. 3 is a cross-sectional side view of an illustrative electronicdevice of the type shown in FIGS. 1 and 2 in accordance with anembodiment of the present invention.

FIG. 4 is a perspective cross-sectional view of the illustrativeelectronic device of FIG. 3 in accordance with an embodiment of thepresent invention.

FIG. 5 is perspective interior view of a portion of a display in adevice of the type shown in FIGS. 3 and 4 in accordance with anembodiment of the present invention.

FIG. 6 is a diagram of a conventional button mounted in an opening in adevice housing.

FIG. 7 is a cross-sectional side view of an illustrative button in anelectronic device in accordance with an embodiment of the presentinvention.

FIG. 8 is an exploded perspective view of an illustrative screw andsupport structure that may be used in supporting a button switch in anelectronic device in accordance with an embodiment of the presentinvention.

FIG. 9 is a perspective view of an interior portion of an electronicdevice housing showing holes that may be provided in the housing toreceive an elongated cylindrical member such as a screw of the typeshown in FIG. 8 in accordance with an embodiment of the presentinvention.

FIG. 10 is an exploded perspective view of an illustrative electronicdevice housing, a button, and button support structures in accordancewith an embodiment of the present invention.

FIG. 11 is a perspective view that shows a button and button supportstructures such as a button and button support structures of the typeshown in FIG. 10 mounted in an electronic device housing such as anelectronic device housing of the type shown in FIG. 10 in accordancewith an embodiment of the present invention.

FIG. 12 is a perspective view of an illustrative electronic device thatmay have a spring-loaded clip and structures in the clip to providedurability in accordance with an embodiment of the present invention.

FIG. 13 is an exploded perspective view of an electronic device of thetype shown in FIG. 12 in accordance with an embodiment of the presentinvention.

FIG. 14 is a cross-sectional side view of a portion of an electronicdevice of the type shown in FIGS. 12 and 13 in the vicinity of a springin accordance with an embodiment of the present invention.

FIG. 15 is an exploded perspective view of an electronic device of thetype shown in FIG. 12 in accordance with an embodiment of the presentinvention.

FIG. 16 is an exploded perspective view of an illustrative electronicdevice that has a display in accordance with an embodiment of thepresent invention.

FIG. 17 is a top view of a portion of an electronic device housingshowing how the housing may have a ledge on which a cover layer in adisplay may rest in accordance with an embodiment of the presentinvention.

FIG. 18 is a perspective view of an interior portion of an electronicdevice of the type shown in FIG. 16 showing how a support structure maybe used to bridge gaps in a housing ledge in accordance with anembodiment of the present invention.

FIG. 19 is a cross-sectional side view of a portion of the housing ofFIG. 18 taken through an illustrative portion of a housing ledge thatdoes not have a gap in accordance with an embodiment of the invention.

FIG. 20 is a cross-sectional side view of a portion of the housing ofFIG. 18 taken through an illustrative portion of a housing ledge thathas a gap and an associated display support structure in accordance withan embodiment of the invention.

FIG. 21 is a perspective view of an illustrative electronic device thatmay be provided with a display cover layer in accordance with anembodiment of the present invention.

FIG. 22 is a cross-sectional side view of an illustrative electronicdevice of the type shown in FIG. 21 taken along a central portion of adisplay edge in accordance with an embodiment of the present invention.

FIG. 23 is a cross-sectional side view of an illustrative electronicdevice of the type shown in FIG. 21 taken at a corner portion of adisplay edge in accordance with an embodiment of the present invention.

FIG. 24 is a perspective view of a housing for an electronic device ofthe type shown in FIG. 21 showing how corner portions may be removedfrom a housing ledge on which the edges of a display cover layer aremounted in accordance with an embodiment of the present invention.

FIG. 25 is a perspective view of a housing for an electronic device ofthe type shown in FIG. 21 showing how corner portions may be removedfrom a housing ledge on which the edges of a display cover layer aremounted in accordance with an embodiment of the present invention.

FIG. 26 is a perspective view of an illustrative spacer and flex circuitin accordance with an embodiment of the present invention.

FIG. 27 is a cross-sectional end view of an illustrative spacer to whicha flex circuit has been attached in accordance with an embodiment of thepresent invention.

FIG. 28 is a side view showing how layers of flex circuit material maybe bonded together to form a flex circuit and showing how a stiffenermay be thermally bonded to the flex circuit using a heated press inaccordance with an embodiment of the present invention.

FIG. 29 is a side view of a screen printing tool of the type that may beused in forming a patterned adhesion promotion layer such as a patternedcoating of ink on the surface of a flex circuit in accordance with thepresent invention.

FIG. 30 is a side view of an oven that is being used to heat a flexcircuit with a patterned adhesion promotion layer of the type that maybe formed using the equipment of FIG. 29 in accordance with anembodiment of the present invention.

FIG. 31 is a side view of an illustrative spacer to which a flex circuitis being attached using ultraviolet-light-cured adhesive that is beinglaunched into the interior of the spacer in accordance with anembodiment of the present invention.

FIG. 32 is a flow chart of illustrative steps involved in attaching aflex circuit to a support structure in accordance with an embodiment ofthe present invention.

DETAILED DESCRIPTION

Electronic devices are sometimes provided with displays. Displays may beused to present visual information to a user such as pictures and menuitems. If desired, displays may be provided with touch sensors to gatheruser touch input.

A perspective view of an illustrative electronic device that may beprovided with a display is shown in FIG. 1. As shown in FIG. 1, device100 may have a housing such as housing 102. Housing 102 may be formedfrom plastic, metal, carbon fiber composite material, other composites,glass, ceramics, other materials, or combinations of these materials.Housing 102 may be formed from multiple pieces of material or may beformed using a unibody construction in which housing 102 issubstantially formed from a single structure (e.g., machined or castmetal, plastic, etc.). Device 100 may be a media player, a cellulartelephone, a computer, or other suitable electronic device.

Display 104 may be mounted to the front face of device 100. Portions ofhousing 102 such as portions 128 may surround display 104. Portions 128may be integral portions of housing 102 or may be separate structures.For example, portions 128 may be provided by creating a rectangular lipin housing 102 that surrounds all four edges of display 104 or, ifdesired, portions 128 may be formed from a separate rectangular ringmember that is attached to other housing structures. Portions 128 mayserve as a cosmetic trim for display 104 and may sometimes be referredto as a bezel structure or a device bezel.

To improve device aesthetics and reduce device size, it may be desirableto minimize the width of bezel 128. At the same time, sufficientinterior space should be provided within device 100 to accommodate thecomponents that make up display 104. A cross-sectional side view of anillustrative layout that may be used to mount display 104 and itsassociated structures within device 100 is shown in FIG. 2. As shown inFIG. 2, display 104 may include multiple layers such as layers 110, 108,and 106. These layers may form an image pixel array for displayingimages for a user. The layers may include a touch sensor array based oncapacitive sensors, resistive sensors, acoustic sensors, piezoelectricsensors, or other sensors.

As shown in FIG. 2, the exposed outer surface of display 104 may becovered with a transparent protective member such as planar transparentcover layer 106. Layer 106 may be formed from plastic, glass, ceramic,or other transparent substances. In a typical scenario, layer 106 may beformed from glass. Layer 106 may therefore sometimes be referred to as acover glass layer. The use of glass to form protective cover layer 106is, however, merely illustrative. Other materials may be used inprotective layer 106 if desired.

Display 104 may be an organic light-emitting diode (OLED) display, aplasma display, a liquid crystal display (LCD) or other suitabledisplay. The use of LCD technology is sometimes described herein as anexample.

In an LCD display arrangement, layer 110 may include a thin-filmtransistor layer. The thin-film transistor layer may include an array ofthin-film transistors formed on a glass substrate. Layer 108 may be acolor filter layer that includes an array of colored filter elements.Touch sensor layers may also be incorporated into layer 108 or may beplaced adjacent to layer 108. A layer of liquid crystal material may beinterposed between layer 108 and layer 110. Electrodes may be used toapply electric fields to image pixels in the liquid crystal layer.Thin-film transistor circuitry on the thin-film layer may be used indriving signals onto the electrodes. A backlight structure and otherstructures may also be included in display 104.

Driver integrated circuit (IC) 120 may be formed on the outermostsurface of thin-film transistor layer 110 (i.e., on the outermostsurface of a thin-film transistor substrate layer). Thin-filmtransistors and other circuitry for display 104 may be formed on theoutermost surface of thin-film transistor layer 110 in the portion ofdisplay 104 that is adjacent to color filter layer 108. This circuitryforms an array of image pixel circuits for an image pixel array indisplay 104. Conductive traces on the surface of layer 110 may be usedto interconnect driver IC 120 to the thin-film transistors in the imagepixel array. It is generally desirable to form driver IC 120 on thesurface of layer 110 to ensure that control signals from driver IC 120can be driven into the image pixel array without experiencingundesirable parasitic capacitances.

Device 100 may have one or more printed circuit boards such as printedcircuit board 112. Circuit board 112 may be formed from a rigid printedcircuit board material such as fiberglass-filled epoxy (as an example).Integrated circuits and other components 130 may be mounted on printedcircuit board 112. To interconnect the circuitry of board 112 to display104, a cable such as cable 114 may have one end (end 116) that isconnected to board 112 and may have another end (end 118) that isconnected to thin-film transistor layer 110. Cable 114 may, if desired,be implemented using a flexible printed circuit (“flex circuit”) formedfrom a sheet of flexible polymer such as polyimide. Flex circuit cable114 may include a number of conductive traces. Each end of flex circuitcable 114 may be provided with contacts that make electrical connectionswith mating contacts on board 112 and thin-film transistor layer 110.Connector structures (e.g., flex circuit connectors) may be used inconnecting flex circuit cable 114 to traces on board 112 at end 116 andin connecting flex circuit cable 114 to thin-film transistor layer 110at 118. Connections between cable 114 and the conductive traces on board112 and thin-film transistor layer 108 may also be formed usingconductive adhesive (sometimes referred to as anisotropic conductivefilm).

Edge 132 of color filter layer 108 (i.e., the color filter glasssubstrate and any touch sensor electrode substrate and other touchsensor structures that are adjacent to the color filter glass substrate)is preferably recessed by a distance R with respect to edge 124 ofthin-film transistor layer 110. This serves to form an exposed region inthin-film transistor layer 110 upon which driver IC 120 may be mounted.The exposed region preferably has a sufficient area to accommodatedriver IC 120 and attachment of end 118 of flex circuit cable 114.

To minimize the size of bezel region 128 of housing 102, housing 102 mayhave a protruding structure such as structure 126. Protrusion 126 servesas a support structure for cover layer 106. On the left-hand edge ofcover layer 106 (in the orientation of FIG. 2), pressure sensitiveadhesive 122 may be used to attach cover layer 106 to protrusion 126.Along the other edges of cover layer 106 (e.g., along the right-handedge of cover layer 106 in the orientation of FIG. 2), pressuresensitive adhesive 122 may be used to connect cover layer 106 to otherportions of housing 102. To facilitate assembly, the pressure sensitiveadhesive that is used to attach cover layer 106 may be placed on coverglass 106 along the left-hand edge prior to assembly and may be placedon housing 102 along the other three edges. Attaching the pressuresensitive adhesive to cover glass 106 along its left-hand edge may helpprevent the left-hand edge of cover glass 106 from catching on thepressure sensitive adhesive during assembly.

Because structure 126 has the shape of a protrusion, the region directlybelow protrusion 126 forms a cavity that can be used to accommodatecomponents in device 100 such as display components. As shown in FIG. 2,for example, there is a region 134 that lies under protrusion 126 (i.e.,a region that is located in a more interior location within housing 102than protrusion 126) and that is available for internal devicecomponents. In the FIG. 2 example, cavity region 134 is used toaccommodate the left-hand edge of thin-film transistor glass 110, flexcircuit cable 114, and the left-hand edge of printed circuit board 112.If desired, other components may be mounted under housing protrusion 126in region 134. The FIG. 2 arrangement is merely illustrative.

FIG. 3 is a cross-sectional side view of an illustrative arrangementthat may be used for electronic device 100. As shown in FIG. 3, displaylayers 104 may include cover glass 106, optically clear adhesive 152,touch sensor array 150 (e.g., a glass substrate with an array of clearelectrodes such as indium tin oxide electrodes), optically clearadhesive 146, upper polarizer 148, color filter layer 108, thin-filmtransistor layer 110, and lower displayer layers 154 (e.g., backlightstructures including a back reflector and diffuser layer, a lowerpolarizer, etc.).

Flex cable 114 may have a bend such as bend 142. Support structure 138may help support flex cable 114 at bend 142 (e.g., by ensuring that flexcable 114 has a defined minimum acceptable bend radius). Stiffeners suchas stiffener 140 may be used in supporting flex cable 114 (e.g., toprevent bends that would weaken solder joints on cable 114). Stiffener140 may be, for example, a metal stiffener that is formed from amaterial such as stainless steel. Support structure 138 may be formedfrom a material such as plastic. For example, support structure 138 maybe formed from polycarbonate. Bracket 136 may be formed from a metalsuch as stainless steel and may be used for mounting plastic supportstructure 138. Adhesive 156 may be used in attaching flex circuit cable114 to support structure 138.

Electrical components such as capacitors 160 may be mounted to flexcircuit cable 114 and may be accommodated (along with the otherstructures shown in FIG. 3) within cavity region 134 under protrusion126. FIG. 4 is a cross-sectional perspective view of device 100 showinghow capacitor 160 may be mounted in the cavity under protrusion 126.

As shown in FIG. 3, portions of display 104 such a portion 162 ofbacklight layers 154 (sometimes referred to as a p-chassis) may also beaccommodated in the cavity (i.e., cavity region 134) that is formedbelow the overhanging protrusion (protrusion 126).

Air gaps such as air gaps 144 and cover layer lower chamfer 158 may helpprevent damage to cover layer 106. Cover layer 106 may have an uppersurface that is raised above the uppermost surface of housing 102.

A perspective view of cover layer 106 and associated components asviewed from the interior of device 100 (in an unassembled state) isshown in FIG. 5. As shown in FIG. 5, flex circuits such as circuits 114and 114′ may be provided with bends and may have portions that runvertically (i.e., parallel to vertical axis 164, which is perpendicularto the plane of planar cover layer 106 and the other planar layers ofplanar display 104).

Electronic devices often contain buttons. For example, buttons may beused to make volume adjustments and other media playback adjustments, tomake menu selections, to turn the power in a device on and off, and toprovide other control functions.

A conventional button is shown in the cross-sectional side view of FIG.6. As shown in FIG. 6, button 200 is formed in an opening in electronicdevice housing 202. Button 200 has button member 204 that reciprocatesalong axis 222 during operation. When pressed downwards in direction224, lower button member surface 210 presses against upper portion 212of dome switch 214. This collapses dome switch 214 and shorts electricalcontacts associated with dome switch 214, “closing” the switch.

Dome switch 214 is mounted on dome switch support member 216. Domeswitch support member 216 is attached to the interior surface 226 ofhousing wall 202 using adhesive 220.

To ensure proper operation of button 200, the dimensions of thestructures in FIG. 6 should be well controlled. In particular, thespacing between lower surface 210 of button member 204 and upper surface212 of dome switch 214 should be accurately controlled. If this spacingis too small, switch 214 may be inadvertently activated. If this spacingis too large, the button may feel loose or it may be difficult toproperly close the switch when button member 204 is moved in direction224.

The distance between lower surface 210 and upper surface 212 isdetermined by the location of surface 212 and the location of surface210.

The location of surface 212 relative to housing 202 is affected by thelocation of inner surface 226 of housing wall 202 and the shape ofsupport 216. This is because surface 218 of support 216 is attached tosurface 226. Variations in the location of surface 226 affect thelocation of surface 218 and therefore the location of surface 212 ofswitch 214.

The location of surface 210 relative to housing 202 is affected by thelocation of surface 208 of housing 202. This is because surface 206 ofbutton member 204 bears against surface 208 when button member 204 isnot depressed. Careful control of the location of surfaces 226 and 208and use of accurate dimensions in support structure 216 will ensure thatbutton 200 functions properly.

In compact button designs, there may not be sufficient space availableto accommodate a button support structure such as conventional supportstructure 216 of FIG. 6. A button arrangement of the type shown in FIG.7 may therefore be used to ensure accurate button operation.

As shown in FIG. 7, button 250 may be formed from a button member suchas button member 254 that is mounted in an opening in electronic devicehousing 252. Button 250 may be actuated when a user presses on surface284 in direction 282. This pushes button member 254 in direction 282 sothat inner button member surface 286 presses against outermost surfaceportion 260 of dome switch 262. When dome switch 262 is collapsed, aconductive inner dome surface in switch 262 may short a pair of switchterminals to each other, thereby closing the switch.

The distance between surface 286 of button member 254 and surface 260 ofdome switch 262 affects the operation of button 250. Accurate buttonoperation may be achieved by accurately controlling this distance.

The distance between surface 286 and surface 260 is controlled by thelocation of surface 286 and the location of surface 260.

The location of surface 286 relative to housing 252 is affected by thelocation of inner surface 256 of housing wall 252. This is becausesurface 258 of button member 254 bears against surface 256 when buttonmember 254 is not depressed (i.e., when button member 254 is in itsunactuated position).

The location of surface 260 of dome switch 262 relative to housing 252is controlled by the location of surface 270 of support structure 288.This is because dome switch 262 and its associated flex circuitsubstrate 272 are mounted on surface 270 (e.g., using pressure sensitiveadhesive). The location of surface 270 along dimension 280 thereforecontrols the location of surface 260 along dimension 280.

To ensure that the location of surface 270 is well controlled relativeto housing 252, support structure 288 may be mounted within electronicdevice housing 252 (and the electronic device formed using housing 252)using one or more elongated members such as screw 264.

Screw 264 may have a head such as head 290 that is attached to a shaftsuch as shaft 276. Portion 278 of shaft 276 may be smooth (unthreaded)and may pass through an unthreaded cylindrical opening with smoothsidewalls in portion 252′ of housing 252. Portion 266 of shaft 276 maybe threaded and may engage threads in support structure 288. Portion 274of shaft 276 may be smooth (unthreaded) and may be received in anunthreaded cylindrical opening in housing 252.

The outer diameter of shaft 276 in regions 278 and 274 and thecorresponding inner diameter of the openings through support structure288 and housing 252 can be accurately controlled during manufacturing,which allows the position of surface 270 along dimension 280 (andtherefore the position of surface 260) to be accurately determined.

FIG. 8 is an exploded perspective view showing how screws such as screw264 may be inserted into holes such as hole 300 in support structure 288along an axis such as axis 294. FIG. 8 also shows how dome switch 262and dome switch flex circuit 272 to which dome switch 262 is connectedmay be mounted on front surface 270 of support structure 288. A layer ofadhesive such as pressure sensitive adhesive 302 may be used inattaching flex circuit 272 to support 288. Front surface 270 may be aplanar surface that lies parallel to longitudinal axis 294 of screw 264.

FIG. 9 is a perspective view of a portion of housing 252 showing howhousing 252 may have an opening such as opening 298 to accommodatebutton member 254. As shown in FIG. 9, screw 264 (FIG. 8) may passthrough opening 292 in housing portion 252′ along axis 294. Wheninserted through opening 292 of housing portion 252′ and through opening300 in support structure 288 of FIG. 8, tip portion 274 of screw 264will be received within hole 296 in housing 252, thereby holding supportstructure 288 and dome switch 262 in place within device housing 252.Device housing 252 may form a housing for an electronic device such as acellular telephone, music player, computer, or other electronicequipment.

FIG. 10 is an exploded perspective view of buttons such as button 250 ofFIGS. 7, 8, and 9 that may be mounted in an electronic device (such asdevice 100 of FIG. 1). As shown in FIG. 10, device 100 may include threebuttons of the type shown in FIGS. 7, 8, and 9. Dome switches 262A,262B, and 262B for the three buttons may be mounted on a circuit such asflex circuit 712. Flex circuit 712 may be connected to circuitry indevice 100. As one example, flex circuit 712 may be connected to circuit711. Circuit 711 may, if desired, be connected to audio jack connector710.

Support structure 288 may include four holes 300 with threads. Screws264 may screw into holes 300 and engage the threads of holes 300.

Device 100 may include openings in device housing 252 such as openings700, 702, 704A, 704B, and 704C. As examples, opening 700 may be anopening for a 30-pin connector, opening 702 may be an opening for anaudio plug, opening 704A may be an opening for button member 254A (e.g.,a lock/unlock button), opening 704B may be an opening for button member254B (e.g., an up button that may be used as a volume up button), andopening 704C may be an opening for button member 254C (e.g., a downbutton that may be used as a volume down button).

Button members 254A, 254B, and 254C may be respectively biased intoopenings 704A, 704B, and 704C of device housing 252.

A perspective view of the buttons and electronic device of FIG. 10 in anat least partially assembled state is shown in FIG. 11. As shown in FIG.11, flex circuit 712 may include portions that wrap around supportstructure 288. If desired, flex circuit 712 may be coupled to supportstructure 288 (e.g., flex circuit 712 may be coupled to supportstructure 288 with adhesive).

Electronic devices may be provided with spring-loaded clips. Forexample, small portable devices such as music player devices may beprovided with clips that allow the devices to be attached to articles ofclothing.

FIG. 12 is a perspective view of an illustrative electronic device thatmay be provided with a clip. Electronic device 400 of FIG. 12 may be amedia player, a cellular telephone, or other electronic equipment. Asshown in FIG. 12, electronic device 40 may have a main body such ashousing 402. Housing 402 may be formed from one or more structures suchas plastic structures, metal structures, glass structures, compositestructures, ceramic structures, or combinations of such structures.Housing 402 may include control circuits, a battery, and user interfacecomponents (e.g., buttons, displays such as touch screen displays andnon-touch displays, status indicator lights, speaker and microphoneports, audio jacks, input-output port connectors, etc.).

Device 400 may have a clip such as clip 404. Clip 404 may have a clipmember such as clip member 450. Hinge 406 and hinge pin 408 may allowclip member 450 to pivot about clip rotational axis 410. When a userpresses end 412 of member 450 towards housing 402 in direction 414, end416 of member 450 is forced away from housing 402 in direction 418. Thisopens gap 422 to receive an item of clothing or other object. When end412 is released, a spring in hinge 406 may bias member 450 so that end416 moves in direction 420 towards housing 402 and grips the item ofclothing or other object within gap 422.

The spring in hinge 406 may be a torsion spring such as torsion spring428 in FIG. 13. Spring 428 may be formed from music wire having adiameter of 0.65 mm (as an example). As shown in FIG. 13, housing 402may include structures 402A and 402B. Structure 402A may be a cover, adisplay, a control panel, or other structure. Structure 402B may be alower housing body structure in which printed circuit boards and othercomponents for device 400 are mounted.

Screws 424 may pass through holes 452 in housing 402B and may bereceived by threaded holes 454 in hinge block structure 426. Thisattaches hinge block structure 426 to housing 402B.

Member 450 may have a tooth structure such as tooth 434 to help member450 when grasping items of clothing. Hinge pin support structure 436 mayhave holes 438 that receive press-fit hinge pins 408 along axis 410.Pins 408 also are received in holes 456 on hinge block structure 426.This holds structure 426 over spring 428 and captures spring 428 betweenstructure 426 and surface 432 of member 450 in hinge structure 436.

Spring 428 may have end portions that engage clip 450 and structure 426.For example, spring 428 may have a bent end such as end 442 that bearsagainst plate 430 on surface 432 of member 450. Spring 428 may also havea bent end such as bent end 440 that engages recess 427 in structure426. Because structure 426 is attached to housing 402B, end 440 is fixedwith respect to housing 402B.

When clip member 450 is rotated around axis 410 to open clip 404, spring428 twists. The torsion that is produced by the twisted shape of spring428 produces a restoring force that tends to close clip 404. For thisreason, hinge 406 may sometimes be referred to as a torsion hinge ortorsion-spring hinge.

As shown in FIG. 14, plate 430 may be attached to clip member 450 by alayer of adhesive such as adhesive 444. Adhesive 444 may be, forexample, a layer of pressure sensitive adhesive that attaches theunexposed underside of plate 430 to member 450. Other attachmentmechanisms may be used if desired (e.g., welds, fasteners, slots, etc.).

When end 412 of member 450 is pushed in direction 414 to open clip 404,exposed surface 446 of plate 430 pushes upwards in direction 414 andbears against end 442 of spring 428. End 440 of spring 428 may bereceived within hole 427 (or other suitable engagement feature) in hingeblock structure 426 and is therefore held at a fixed position withrespect to housing 402B. As torsion builds in spring 428, the pressurebetween end 442 and plate 430 increases.

Plate 430 is preferably formed from a durable material that canwithstand pressure from end 442 of spring 428 without becoming worn. Forexample, plate 430 may be formed from a thin sheet of a hard metal suchas stainless steel. The metal of plate 430 is preferably harder and moredurable than the metal and that forms member 450, thereby enhancing thedurability of member 450 and clip 404. In a typical arrangement, member450 and housing body 402B may be formed from relatively soft materialssuch as aluminum, other soft metals, or other soft materials such asplastic. By forming plate 430 from a material that is harder than member450, the surface of member 450 is protected from wear due to contactwith end 442 of spring 428. Plate 430 may be formed from stainlesssteel, tungsten, molybdenum, stiff alloys of materials such as these, orany other material that is harder than member 450.

FIG. 15 is an exploded perspective view of an electronic device such asdevice 400 of FIG. 12 that may include a clip such as clip 404. As shownin FIG. 15, device 400, housing structure 402B, clip 404, and tooth 434may have rounded edges. Clip 404 may be mounted to housing structure402B using four screws 424 (as an example). Housing structure 402B mayinclude four holes 452 (shown in FIG. 25). Screws 424 may pass throughholes 452 and thread into holes 454 of hinge block structure 426.

Electronic devices that include displays may have housings with ledges(see, e.g., protrusion 126 of FIG. 2, which forms a ledge that supportslip-shaped cover layer 106). The ledges may be used to support the edgesof a display cover layer. It may sometimes be desirable to form gapswithin a ledge. For example, it may be desirable to form a gap in aledge to accommodate a screw or other device component. If care is nottaken, the presence of gaps in the ledge may create a failure point thatmakes the cover layer in the display subject to cracking (i.e., becausethe display cover layer is not supported by the ledge in the gapregion).

This failure mechanism can be at least partly eliminated by providingdisplay support structures. An illustrative device of the type that maybe provided with display support structures within housing ledge gaps isshown in FIG. 16. As shown in FIG. 16, electronic device 500 may includea housing such as housing 508. Housing 508 may be formed using a unibodyconstruction or may be formed from one or more separate housing members.Materials that may be used for forming housing 508 include metal,plastic, carbon fiber composites and other composites, ceramics, glass,other materials, and combinations of these materials. In a typicalarrangement, housing 508 may be formed from a piece of metal that hasbeen machined to form solid or protrusion-shaped ledges (e.g., ledgestructures 510 and associated ledge support surfaces 512).

Device 500 may have a display such as display 534. Display 534 mayinclude a display module such as display module 504. Module 504 mayinclude liquid crystal display (LCD) layers such as color filter andthin-film transistor layers and an optional touch sensor layer. Touchsensor capabilities may be provided using capacitive touch sensors,acoustic touch sensors, piezoelectric touch sensors, resistive touchsensors, or other touch sensors. Display module 504 may be protected bycover layer 502. Cover layer 502 may be formed from a transparent sheetof material such as glass or plastic. Glass structures can provide goodscratch resistance and transparency, but can be subject to cracking ifdevice 500 is dropped. Plastic, ceramics, and other transparent coverlayer material may also be subject to breakage if device 500 is dropped.

When display 534 is mounted in device 500, the periphery of cover layer502 rests on ledge surface 512 of ledge 510 and is surrounded by bezelregion 518. To ensure that display 534 and cover layer 502 aresufficiently protected against damage, weaknesses in the mountingarrangement for display 534 may be reduced or eliminated. One possibleweakness in an arrangement of the type shown in FIG. 16 is the presenceof gaps such as gap 514 in ledge structure 510. Gaps such as gaps 514may be formed to accommodate design constraints (e.g., to make room forscrews such as screws 516 or other components). When gaps 514 arepresent, however, the continuity of ledge surface 512 is disrupted. Thiscreates an unsupported portion along the edge of cover layer 502 thatcan cause layer 502 to crack if device 500 is dropped or subjected toother impact events.

FIG. 17 is a top view of ledge 510 showing how incorporation of gap 514into ledge 510 to accommodate screw 516 results in a discontinuity inledge surface 512.

FIG. 18 shows how device 500 may be provided with support structuressuch as support structures 520. Structures 520 may have shapes withcavities that accommodate screws 516 or other such components. The sizeof structures 520 may be configured so that the upper surface of eachsupport structure 520 lies flush with ledge surface 512. Supportstructures 520 may be attached to housing 508 using pressure sensitiveadhesive or other adhesives, fasteners, engagement features, welds, orother suitable attachment mechanisms. Materials that may be used to formsupport structures 520 include plastic, metal, composites, etc. With onesuitable arrangement, housing 508 may be formed from machined metal suchas machined aluminum and support structures 520 may be formed fromplastic.

Because the upper surface of support structure 520 lies flush with ledgesurface 512 of housing ledge portion 510, the ledge surface thatsupports the periphery of cover layer 502 is substantially continuous.In this respect, support structures 520 serve to help support displaycover layer 502 and may therefore sometimes be referred to as displaysupport structures, cover glass support structures, or cover layersupport structures.

A cross-sectional view of device 500 of FIG. 18 (including display coverlayer 502) that is taken along line 530 of FIG. 18 and that is viewed indirection 532 is shown in FIG. 19. As shown in FIG. 19, in portions ofledge 510 that do not contain gaps, ledge surface 512 supports interiorsurface 524 of cover layer 502.

A cross-sectional view of device 500 of FIG. 18 (including display coverlayer 502) that is taken along line 526 of FIG. 18 and that is viewed indirection 528 is shown in FIG. 20. As shown in FIG. 20, in portions ofledge 510 that contain gaps (gaps 514 of FIGS. 16, 17, and 18), ledgesurface 512 is substantially reduced or is absent and is thereforeunable to support interior surface 524 of cover layer 502. To preventdisplay cover layer 502 from cracking, support for interior surface 524of cover layer 502 may be provided by outer ledge surface 522 of supportstructure 520. Structures 520 are therefore able to bridge gaps in ledge510 and ensure that display cover layer 502 is satisfactorily supportedaround its periphery.

It may be desirable to provide an electronic device with a display coverlayer have a surface that protrudes slightly from the surface of thehousing in which the display cover layer is mounted. FIG. 21 is aperspective view of an illustrative electronic device that may beprovided with a display of this type. As shown in FIG. 21, device 600may have a housing such as housing 602. Housing 602 may be formed fromplastic, metal, carbon fiber composite material, other composites,glass, ceramics, other materials, or combinations of these materials.Housing 602 may be formed from multiple pieces of material or may beformed using a unibody construction in which housing 602 issubstantially formed from a single structure (e.g., machined or castmetal, plastic, etc.).

Display 604 may be mounted to the front face of device 600, so thatouter (exterior) surface 608 of display 604 (i.e., the surface of alayer of display cover material such as display cover glass) is locatedat an elevated distance PX above housing surface 606 (i.e., surfaces 606and 608 are not flush with each other because surface 608 protrudesoutwards past surface 606). Surface 606 may, for example, be associatedwith a bezel structure that serves as a cosmetic trim for display 604, ametal band such as a housing band or other structure that surroundsdisplay 604, a portion of a unibody housing or multipart housing thatsurrounds display 604, or other device structures.

The elevation of surface 608 of display 604 above surface 606 of housing602 may enhance device aesthetics, but may make display 604 more likelyto crack when dropped or subjected to other shock events. In a dropevent, device 600 may strike the ground front-face down (i.e., withdisplay 604 facing the ground). When device 600 falls, one corner ofdisplay 604 may strike the ground before others. This may cause anopposing corner of display 604 to experience a whip-like motion in whichthe opposing corner of display 604 strikes the ground with a magnifiedforce. Particularly in devices such as device 600 of FIG. 21 that haveelevated display surfaces (or other such elevated layers), display 604may be prone to damage if not designed properly.

To prevent damage during drop events, device 600 may have displaymounting ledges that run along only portions of the periphery of device600. Near the corners of device 600 in which display 604 may be subjectto a whip-like strike, the display mounting ledges may be absent toaccommodate potential flexing of display 604 (i.e., flexing in a displaycover layer such as a display cover glass layer). This type ofarrangement is illustrated in more detail in FIGS. 22 and 23. FIG. 22 isa cross-sectional view of the right-hand edge of device 600 of FIG. 21taken along line 628 of FIG. 21 and viewed in direction 630. FIG. 23 isa cross-sectional view of the right-hand edge of device 600 of FIG. 21taken along line 624 and viewed in direction 626.

The cross-sectional view of FIG. 22 corresponds to a portion of device600 in which a display mounting ledge is present and is used to mountdisplay 604. As shown in FIG. 22, display 604 may include cover layer632 and display module structures 612. Display module 612 may includelayers that form an image pixel array for displaying images for a userof device 600. If desired, display module layers 612 may include a touchsensor array based on capacitive sensors, resistive sensors, acousticsensors, piezoelectric sensors, or other sensors. The layers of displaymodule 612 may also include a backlight, polarizers, a color filterlayer, a liquid crystal layer, a thin-film transistor layer, and otherdisplay layers. Display module 612 may be an organic light-emittingdiode (OLED) display module, a plasma display module, a display moduleusing liquid crystal display (LCD) technology, or other suitabledisplay. As shown in FIG. 22, the exposed outer surface of display 604may be covered with a transparent protective member such as planartransparent cover layer 632. Layer 632 may be formed from plastic,glass, ceramic, or other transparent substances. In a typical scenario,layer 632 may be formed from glass. Layer 632 may therefore sometimes bereferred to as a cover glass layer. As with the other electronic devicearrangements described herein, the use of glass to form protective coverlayer 632 is merely illustrative. Other materials may be used inprotective layer 632 if desired.

FIG. 22 shows how the edge of cover layer 632 may have a lower edgesurface such as surface 616 that is mounted on a ledge in housing 602such as ledge surface 620. A layer of adhesive such as pressuresensitive adhesive 610 may be interposed between lower cover layersurface 616 and upper surface 620 of the housing ledge. The housingledge may be formed from a portion of housing 602 such as protrusion602A or other suitable housing structures. Module 612 may have a smallerplanar area than cover layer 632 (i.e., a smaller footprint when viewedfrom the front face of device 600), so that the edges of module 612 aresomewhat recessed from the edges of cover layer 632. Strips of adhesivesuch as pressure sensitive adhesive 610 may run along each of the fourperipheral edges of display 604.

Protrusion 602A and display mounting ledge surface 620 are preferablyabsent from the four corners of device 600, as shown in thecross-sectional view of FIG. 23. As shown in FIG. 23, the inner surfacesof housing 602 in the corners of housing 602 are configured to form acavity (opening 614) under each lower edge surface 616 of display coverlayer 632.

Ledge-shaped protrusion 602A and ledge surface 620 of FIG. 22 (which arepresent along the center of the edges of the display) are not present atthe corners of display 604 and device 600. As a result of the absence ofsupport from an underlying ledge, cover layer 632 is free to flexsomewhat in the event that cover layer 632 experiences an inward forceduring a drop event. If, for example, exposed surface 608 of cover layer632 experiences an inward force because of a drop event, the corner ofcover layer 632 and the associated lower surface 616 in the corner ofdisplay 604 can flex inward in direction 618 without being impeded byprotrusion 602A. Cover layer 632 is then able to rebound withoutcracking after the drop event is over.

The amount of each corner that is free of ledge surface 620 andprotrusion 602A can be, for example, 1-30% of the length of each edge,5-10% of the length of each edge, less than 25% of the length of eachedge, or other suitable amount of the edge length in device 600. FIG. 24shows an illustrative arrangement that may be used for device 600. Asshown in FIG. 1, housing structures such as protrusions 602A or otherportions of housing 602 may serve as ledges that form ledge surfaces620. Each ledge surface may run along a respective edge of housing 602.If desired, surface 620 on each edge may be interrupted by one or moregaps that are filled with support structures as described in connectionwith support structures 520 of FIG. 18. Corner openings (cavities) 614may be formed at each corner of device 600, so that each of the fourcorners of display cover layer 632 are unsupported (as shown in FIG. 23)and do not rest on protrusion 602A of FIG. 22.

FIG. 25 is a perspective view of an electronic device such as device 600of FIG. 21 that may include display mounting ledges that run along onlyportions of the periphery of device 600. FIG. 25 shows an illustrativearrangement in which housing structures such as protrusions 602A orother portions of housing 602 serve as ledges that form ledge surfaces620. In the FIG. 25 example, ledge surface 620A is relatively narrow(e.g., surface 620A may be narrower than ledge surfaces 620B, 620C, and620D), ledge surface 620B is formed in multiple sections (e.g., to allowpassage of screws into openings 621), ledge surface 602C is formed alonga relatively short length of the edge of housing 602 (e.g., surface 602Cmay be shorter in overall length that ledge surfaces 620A, 620B, and620D), and ledge surface 620D may be formed adjacent to opening 620D(e.g., a 30-pin opening).

It may be desirable to use adhesion promotion materials to help securelymount flex circuit structures such as the cable formed from flex circuit114 of FIG. 3 to support structures such as support structure 138. Toensure adequate adhesion between flex circuit 114 and support structure138, a patterned coating of an adhesion promotion material may be formedon the flex circuit.

FIG. 26 is an exploded perspective view of an illustrative supportstructure (sometimes referred to as a spacer) and associated flexcircuit with an adhesion promotion layer. As shown in FIG. 26, supportstructure 138 may have curved surface 803. Surface 803 may help define aknown and acceptable bend radius for bend 142 in flex circuit 114.Support structure 138 may be formed from a material that is transparentto light such as clear polycarbonate, other clear plastics, glass, etc.Support structure 138 may, for example, be formed from optically clearpolycarbonate that is transparent at ultraviolet (UV) wavelengths. Theuse of a UV-transparent material for support structure 138 may helpdistribute ultraviolet light that can be used in curing adhesive (e.g.,UV-cured epoxy or other UV adhesive).

Flex circuit 114 may be formed from one or more sheets of flexibledielectric such as one or more sheets of polyimide or other polymerlayers. Patterned conductive lines such as traces of copper or othermetal may be incorporated into the layers of flex circuit 114 to formsignal pathways for signals in device 100. The patterned lines in flexcircuit 114 may be used to form a serial bus, a parallel bus,radio-frequency transmission lines, paths for control signals, paths fordisplay data, and other electrical paths.

Adhesives such as thermally cured adhesives and light-cured adhesives(e.g., UV adhesives) may be used in attaching flex circuit 114 tosupport structure 138. The process of thermally bonding a structure toflex circuit 114 may involve elevated temperatures. For example,thermal-bonding adhesives may form durable bonds when elevated totemperatures of about 150° C. (e.g., 100° C. or more, 150° C. or more,100-200° C., etc.). At the same time, some structures in device 100(e.g., display structures associated with display 104) may be sensitiveto elevated temperatures. As an example, display 104 may have a lightreflector layer that is subject to warping if elevated to temperaturesabove 70° C.

The use of elevated adhesive curing temperatures may be avoided in somesituations by using UV adhesive. UV adhesive can be cured by applicationof UV light without involving the application of heat. Nevertheless, itmay be difficult or impossible to achieve desired adhesion strengthswhen using UV adhesive to bond structures directly to flex circuit 114,due to the inherently weak nature of UV-adhesive-to-polyimide bonding.

To address this potential bonding weakness and thereby ensure that flexcircuit 114 is well attached to support structure 138, a layer ofadhesion promotion material such as material 800 may be interposedbetween flex circuit 114 and an adhesive that helps bond flex circuit114 to the surface of support structure 138. By using a coating ofmaterial 800, adhesion may be increased sufficiently that UV adhesivecan be used to attach flex circuit 114 to support structure 138,avoiding the need to use potentially damaging elevated temperatures.Adhesion promotion material 800 may be formed from a substance such asink (e.g., a coating of black ink such as Taiyo® SW400 black ink havinga thickness of less than 0.5 mm or less than 0.1 mm or other suitablethicknesses).

The application of ink 800 to flex circuit 114 can increase thebrittleness of flex circuit 114. It may therefore be desirable to limitthe application of ink 800 to portions of flex circuit 114 that are awayfrom bend region 142, where flex circuit 114 is flexed during assembly.As shown in the cross-sectional view of FIG. 27, for example, ink 800can be patterned so as to cover only region 810 along the side ofsupport structure 138, not end region 812 of structure 138 in thevicinity of bend 142.

After ink layer 800 has been formed, an adhesive such as UV adhesive maybe used to attach flex circuit 114 to support structure 138. As shown inFIG. 27, for example, adhesive 806 may be used to attach ink 800 andflex circuit 112 to side 138L of support structure 138. The same type ofbonding approach may be used to attach flex circuit 114 to side 138R ofsupport structure 138 or, as shown in FIG. 27, stiffener 140 may beattached to flex circuit 114 using thermally cured adhesive 802 (e.g.,adhesive that forms a bond upon application of an elevated temperature).With this type of approach, adhesive 802 may form a strong bond betweenstiffener 140 and flex circuit 114. Stiffener 140 may be formed from amaterial such as stainless steel, plastic, glass, or other materialsthat exhibit satisfactory adhesion to UV adhesive. This allows stiffener140 may be attached to surface 138R of support structure 138 usingadhesive 804 such as UV adhesive. Because adhesive layers such asadhesive layer 806 on surface 138L and adhesive layer 804 on surface138R of support structure 138 can be formed using UV adhesive, it is notnecessary to subject support structure 138 or the other structures indevice 100 (e.g., display structure 104) to elevated temperatures whenattaching flex circuit 114 to support structure 138 in device 100.

FIGS. 28, 29, 30, and 31 show equipment and processes that may be usedin attaching flex circuit 114 to support structure 138.

To form desired electrical pathways in flex circuit 114, one or morelayers of flex circuit 114 may be provided with patterned traces such astraces 814 of FIG. 28. Flex circuit 114 may be formed from one or morelayers of polyimide or other polymers (as examples). Stiffener 140 maybe attached to the uppermost layer of flex circuit 114 using thermallycuring adhesive 802. The layers of flex circuit 114 may be bondedtogether (e.g., using adhesive) while stiffener 140 is attached to theuppermost layer of flex circuit 114 by application of heat and pressure.For example, heated plates 816 of a heated press may be moved towardseach other to compress and bond together stiffener 140, thermal adhesive802, and the individual layers of flex circuit 114. Heated plates 816may raise the temperature of adhesive 802 to a temperature of about 100°C., to about 150° C., or to other temperatures sufficient for curingthermal adhesive 802.

After flex circuit 114 and bonded stiffener 140 are removed from theheated press, a patterned layer of ink or other adhesion-promotion layermay be formed on flex circuit 114. As shown in FIG. 29, for example,squeegee 818 may be moved in direction 822 to force ink 800 throughpatterned openings such as opening 824 in screen 820. This deposits ink800 in a pattern (e.g., a rectangular shape of the type shown in FIG.26) on the upper surface of flex circuit 114.

An oven or other heating tool may then be used to heat and dry layer800, so that layer 800 forms a satisfactory bond to flex circuit 114(see, e.g., oven 826 of FIG. 30).

Once patterned ink layer 800 has been formed on flex circuit 114, flexcircuit 114 may be attached to support structure 138 using layers ofadhesive such as UV adhesive layer 806 and UV adhesive layer 804 of FIG.31. Light source 828 (e.g., a UV light source such as a UV lamp) may beused to introduce UV light 830 into the interior of support structure138. Support structure 138 may be formed from a material with sufficienttransparency to allow a substantial fraction of the light that has beenlaunched into support structure 138 to pass into UV adhesive layers 804and 806. As light 830 illuminates layers 804 and 806, the adhesive oflayers 804 and 806 is cured. Using this approach, adhesive 806 canattach ink 800 and flex circuit 114 to surface 138L of support structure138. Adhesive 804 can attach stiffener 140 and flex circuit 114 tosurface 138R of support structure 138. Tip region 812 at the end ofsupport structure 138 near bend 142 may be ink free to help avoid makingflex circuit 114 undesirably brittle where flex circuit 114 is beingflexed to bend around support structure 138.

Illustrative steps involved in using equipment of the type shown inFIGS. 28, 29, 30, and 31 to attach a flexible structure such as flexcircuit 114 to a support structure such as support structure 138 areshown in FIG. 32.

At step 832, layers of polyimide or other sheets of flexible materialthat contain patterned conductive traces may be bonded together (e.g.,using a tool such as a press with plates 816 of FIG. 28). Stiffener 140may be thermally bonded to flex circuit 114 by heating plates 816 to anelevated temperature (e.g., above 70° C., about 150° C., etc.).

At step 834, patterned ink layer 800 may be formed on flex circuit 114.Patterned ink 800 may be formed by screen printing, pad printing, brushapplication, spraying, dripping, ink-jet printing, etc. An oven such asoven 826 may be used to bake ink 800 to flex circuit 114.

To complete the assembly of support structure 138 and flex circuit 114into device 100 (as shown, for example, in FIG. 3), UV-curable liquidadhesive layers 804 and 806 may be formed on support structure 138 andflex circuit 114 may be wrapped around end 142 of support structure 138(step 836). Some or all of the wrapping operations involved in bendingflex circuit 114 around end 142 of support structure 138 may occur aftersupport structure 138 has been mounted within the housing of device 100.For example, flex circuit 114 may be wrapped around support structure138 when assembling components within the housing of device 100 such ascomponents that are attached to the ends of flex circuit 114 (e.g., adisplay, display driver circuits, logic boards, etc.).

During the operations of step 836, adhesive layers 804 and 806 may becured by exposure to UV light 830 from UV light source 828 (e.g., afterflex circuit 114 and support structure 138 have been placed withindevice 110). No elevated temperatures are needed to UV cure layers 804and 806, so flex circuit 114 may be attached to support structure 138without elevating the temperature of device 100 and potentially fragilestructures such as display 104.

The foregoing is merely illustrative of the principles of this inventionand various modifications can be made by those skilled in the artwithout departing from the scope and spirit of the invention. Theforegoing embodiments may be implemented individually or in anycombination.

What is claimed is:
 1. An electronic device configured to attach to auser, the electronic device having a front surface, a rear surfaceopposite the front surface, and edge surfaces that extend between thefront surface and the rear surface, the electronic device comprising: ahousing that forms the edge surfaces and at least a portion of the rearsurface, wherein at least one of the edge surfaces is curved, whereinthe housing has an opening, and wherein the housing comprises a ledgethat extends into the opening; an OLED display attached to the ledge,wherein the OLED display covers the opening and forms the front surface,wherein the OLED display is configured to display visual information tothe user, and wherein the visual information includes pictures and menuitems; a button attached to one of the edge surfaces; and an attachmentmechanism mounted to the housing, wherein the attachment mechanismcontacts the housing at a first contact point and a second contactpoint, wherein a portion of the attachment mechanism between the firstand second contact points is separated from the rear surface by a gap,and wherein the attachment mechanism is configured to attach theelectronic device to the user.
 2. The electronic device defined in claim1 wherein the attachment mechanism and the rear surface of the housingform a loop between the first and second contact points.
 3. Theelectronic device defined in claim 2 wherein the loop is configured tobe closed to attach the electronic device to the user.
 4. The electronicdevice defined in claim 1 wherein the attachment mechanism is configuredto be adjusted to change a size of the gap between the attachmentmechanism and the second surface.
 5. The electronic device defined inclaim 4 wherein the attachment mechanism is configured to attach to theuser at the gap.
 6. The electronic device defined in claim 1 wherein thebutton is configured to make menu selections from the displayed menuitems.
 7. The electronic device defined in claim 1 wherein the OLEDdisplay is a touch screen display.
 8. The electronic device defined inclaim 7 further comprising: a flex circuit interposed between thedisplay and the rear surface of the housing, wherein the flex circuit isattached to an interior surface of the ledge.
 9. The electronic devicedefined in claim 7 wherein the touch screen display comprises a coverlayer and wherein the cover layer protrudes from the housing.
 10. Awearable electronic device configured to attach to a user, the wearableelectronic device having a front surface, a rear surface opposite thefront surface, and edge surfaces extending between the front surface andthe rear surface, the wearable electronic device comprising: a housingthat forms the edge surfaces and at least a portion of the rear surface,wherein at least one of edge surfaces is curved, wherein the housing hasan opening, and wherein the housing comprises a ledge extending into theopening; a touch-screen display attached to the ledge, wherein thetouch-screen display covers the opening and forms the front surface,wherein the touch-screen display comprises a cover layer, and whereinthe cover layer protrudes from the housing; and an attachment mechanismmounted to the housing, wherein the attachment mechanism contacts thehousing at first and second points, wherein the first and second pointsare formed adjacent to two opposing edge surfaces, wherein theattachment mechanism is separated from the rear surface of the housingby an adjustable gap between the first and second points, and whereinthe attachment mechanism is configured to attach the wearable electronicdevice to the user.
 11. The wearable electronic device defined in claim10 wherein the attachment mechanism is configured to attach the wearableelectronic device to the user at the adjustable gap.
 12. The wearableelectronic device defined in claim 10 further comprising: a buttonstructure mounted to one of the edge surfaces, wherein the button isconfigured to provide an input to the electronic device.
 13. Thewearable electronic device defined in claim 10 wherein the attachmentmechanism comprises a loop between the first and second points.
 14. Thewearable electronic device defined in claim 13 wherein the size of theadjustable loop is adjustable and wherein the loop is configured to beclosed to attach the electronic device to the user.
 15. The wearableelectronic device defined in claim 10 wherein the touch-screen displaycomprises an OLED display that is configured to display pictures andmenu items.
 16. The wearable electronic device defined in claim 10wherein the cover layer comprises glass.
 17. An electronic deviceconfigured to attach to a user, the electronic device having a firstsurface, a second surface opposite the first surface, and a plurality ofedge surfaces between the first and second surfaces, the electronicdevice comprising: a housing that forms the plurality of edge surfacesand at least a portion of the second surface, wherein the housing has anopening and wherein the housing comprises a ledge that extends into theopening; a touch-screen display attached to the ledge, wherein thetouch-screen display covers the opening and forms the first surface, andwherein the touch-screen display is configured to display a set of menuitems; a button mounted to one of the edge surfaces, wherein the buttonis configured to make menu selections from the displayed set of menuitems; and an attachment mechanism attached to the housing at first andsecond contact points, wherein the attachment mechanism is separatedfrom the housing by a gap between the first and second contact points toform a loop, and wherein the attachment mechanism is configured toattach the electronic device to the user.
 18. The wearable electronicdevice defined in claim 17 wherein the attachment mechanism isconfigured to attach the electronic device to the user with the loop.19. The electronic device defined in claim 18 wherein the loop isconfigured to be adjusted by adjusting a distance between the attachmentmechanism and the housing.
 20. The electronic device defined in claim 18wherein the loop is configured to be closed to attach the electronicdevice to the user.